Roadside Management Toolbox: Asphalt Concrete

AsphaltAsphalt being laid

What is This Treatment?

Asphalt concrete (AC) is a standard Type B asphalt concrete mixed, spread and compacted as noted in the Caltrans standards. Base material (4 -8 inches) and AC depth (2 - 6 inches) will vary depending on site specific requirements.

Where to Use This Treatment?

Asphalt concrete (AC) pavement is recommended for use as a roadside management strategy in medians, gore areas, and in narrow strips adjacent to sound walls and retaining walls. AC is most effective and context appropriate in urban and suburban areas where the roadside AC will be contiguous to the roadway. Asphalt concrete paving may be patterned and/or colored during installation (see Stamped Asphalt Concrete).


  • AC paving is a commonly used road construction material and readily available in most locales.
  • Most contractors and Caltrans Maintenance crews have the equipment and construction knowledge for proper installation.


  • Because it is a rigid material, AC paving is not recommended to be placed within 8 inches of guard rail and sign posts. To control weed growth under guard railing, see Vegetation Control (Minor Concrete).
  • AC paving has a relatively low initial installation cost, but is not as cost effective as Minor Concrete when the full lifecycle cost is considered.
  • AC paving not regularly compacted by traffic will degrade faster than AC paving exposed to traffic. Degradation of paving may allow weeds to establish.
  • If the treatment area has restricted access or other limiting factors standard compaction with equipment may not be attainable.
  • Obtaining the correct AC mix for projects with small quantities of AC or night work requirements may prove problematic and expensive.
  • Excavation for base materials may require removal of ADL (Aerially Deposited Lead) and increase costs.


  • 2010 Standard Specification – 39-1.14 Miscellaneous Areas and Dikes
  • 2010 Standard Specification – 39-1.28 Roadside Paving
  • 2010 Standard Special Provision (SSP) 39-1.28 Roadside Paving
  • 2010 Standard Specification – 39-1.29 Soil Treatment
  • 2010 Standard Special Provision (SSP) 39-1.29 Soil Treatment
  • 2006 Standard Specification – 39-7.01 Miscellaneous Areas


  • $18 - $70/yd2 Variable depending on quantity, soil prep., base depth, AC depth and access.
  • BEES Item(s) - TBD

Updated May 24, 2015